Distributions of agrobiont lady beetles (Coleoptera: Coccinellidae) among crop and non-crop habitats within an agricultural landscape in east-central South Dakota, USA

Authors: Hesler, Louis; Beckendorf, Eric

Submitted to: The Journal of Entomological and Acarological Research (JEAR)
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/13/2024
Publication Date: N/A
Citation: N/A

Interpretive Summary: Alternative habitats to predominant corn and soybean fields may help to stem declines of native lady beetles in central North America, but the relative values of various habitats to native lady beetles have not been directly compared. The goal of this two-year study was to compare the abundance and species composition of native agrobiont lady beetles among habitats such as corn, winter grains, prairie, and wooded tracts across three seasons (late spring, summer, and autumn) in eastern South Dakota, USA. Yellow sticky traps were used to sample lady beetles. A total of 797 individuals and 13 species of lady beetles were sampled. The black-spotted pink lady beetle was the most abundant species and found predominantly in corn and arboreal habitats, and the convergent lady beetle was the second-most abundant species and found mainly in prairie and crop habitats. The harlequin lady beetle was sampled only in 2023 in low numbers but showed a preference for arboreal habitat to other habitats. Parenthesis lady beetle preferred winter grain and prairie habitats over corn and arboreal habitats. The polished lady beetle preferred corn to other habitats. The other 10 species were sampled at relatively low numbers. This study was designed to include habitats that would optimize detection of the thirteen-spotted lady beetle, which has declined in recent years, but it was not sampled from any of the habitats. In light of the findings, prospects are discussed for conserving native agrobiont lady beetles that prey on crop pests among habitats within agricultural landscapes in eastern South Dakota.

Technical Abstract: Alternative habitats to predominant corn and soybean fields may help to stem declines of native lady beetles in central North America, but the relative values of various habitats to native lady beetles have not been directly compared. The goal of this two-year study was to compare the abundance and species composition of native agrobiont lady beetles among habitats such as corn, winter grains, prairie, and wooded tracts across three seasons (late spring, summer, and autumn) in eastern South Dakota, USA. Yellow sticky traps were used to sample lady beetles. A total of 797 individuals and 13 species of lady beetles were sampled. Coleomegilla maculata lengi Timberlake was the most abundant species and found predominantly in corn and arboreal habitats. Hippodamia convergens Guérin-Méneville was the second-most abundant species and found mainly in prairie and crop habitats. Harmonia axyridis (Pallas) was sampled only in 2023 in low numbers but showed a preference for arboreal habitat to other habitats. Hippodamia parenthesis preferred winter grain and prairie habitats over corn and arboreal habitats. Cycloneda munda preferred corn to other habitats. The other 10 species were sampled at relatively low numbers. This study was designed to include habitats that would optimize detection of Hip. tredecimpunctata tibialis Timberlake, which has declined in recent years, but it was not sampled from any of the habitats. In light of the findings, prospects are discussed for conserving native agrobiont lady beetles that prey on crop pests among habitats within agricultural landscapes in eastern South Dakota.